The present invention is directed to an exhaust gas silencer which is mounted on the roof of a surface vehicle which pulls a payload, such as a tractor-trailer combination.
The principles and construction of the silencer per se are set forth in U.S. Pat. No. 3,952,823, the disclosure of which is incorporated herein by reference. Generally, the silencer is used to reduce the load imposed on an engine in pumping gases through the engine exhaust system. The silencer is shaped so that air flowing past the silencer will extract exhaust gases through a gas exit which is a long narrow aperture.